Tennessee Oilers wide receiver Yancey Thigpen hyperextended his left knee during practice Wednesday and was carted off the field.
The two-time Pro Bowl player was running a passing route when he went down. He was examined by a team doctor and sent to an area hospital for a MRI.
Coach Jeff Fisher refused to speculate on how serious the injury could be.
"I've seen this happen on the field and guys come back and practice the next day," Fisher said. "I'm just not going to comment on it any further."
Fisher said the results of the tests and Thigpen's status for Sunday's game with the Chicago Bears (2-5) would be made public sometime Thursday.
Thigpen originally had been listed as questionable for the Bears' game because of a sore groin. He was deactivated for last weekend's victory over the Cincinnati Bengals, the first game he had missed since signing a five-year, $21 million contract with the Oilers in February.
He played in only six games in 1996 while with the Pittsburgh Steelers due to hamstring and foot injuries.
© 1998 SportsLine USA, Inc. All rights reserved